Number 12 sings about the different shapes and arrays that they can become.

The even numbers share all the ways that they can become rectangles though their arrays at their yoga session.

Number 9 sing about the rows that make his number.

Number 8 figures out how many more blocks are needed to make number 14 to balance the bridge.

Numberblocks 16,17, 18, 19, and 20 try to break into a museum by unlocking the doors. To do so, they use their number sheets to figure out the best combinations to open the doors.